The proposed research is a continuation of an ongoing research project which is concerned with applying human factors research techniques to perform a person capability-task demand analysis of daily living tasks. The objectives of the proposed study are to build on this analysis and develop and validate a functional assessment protocol which assesses instrumental capabilities relevant to the performance of daily living activities. The develoment of the protocol will be based on a systems view of task performance which conceives of a task as a series of interdependent, goal-directed, person-environment transactions. Specifically, protocol development will involve task analysis of existing video-tape data of a sample of older adults performing ADL activities, objective measurement of living environments and products used in task performance and computer simulation modeling (content validity) on a sample of older adults stratified on the basis of ADL impairment. In addition to the development of a valid, reliable and feasible task based assessment tool, this protocol will serve as a vehicle for identifying problems older people encounter in the performance of daily living tasks. This will, in turn, target specific areas for intervention as well as identify potential intervention strategies. The overall goal of the project is to yield information which can be used to enhance the functional independence of older adults.